And in the meantime, as the president prepares to make his case to the american people, wall street already revealing it is not convinced about a u.S. Strike. Millions of americans and their 401(k)s ALREADY FEELING THIS, Even before any possible action. So, I want to bring in abc's chief business and economics correspondent, rebecca jarvis, who is with me here tonight. We already saw how wall street is, in real time on this. Reporter: David, this is issue number one for the stock market. If you look at this, the stock market responding almost immediately, where you see on the left-hand side of your screen, the comments from putin, that russia would be backing syria and not the united states, a 150-point drop in the dow, because of that. So, you can see, david, how pivotal this week will be as the u.S. Makes decisions about what its role will be in syria. Wall street will be watching. A huge drop with just word from putin on syria. In the meantime, the other concern, you say, oil prices, already at what, a two-year high? Reporter:110 a barrel. And right now, americans are paying $3.57 at the pump. You could see that go up, with any type of military intervention, because this is a part of the world that controls about a third of our supply.

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